Which of the following does not represent a correct application of the coordination compound?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → desferrioxime B is used in treatment of lead poisoning
In chelate therapy a chelating ligand binds a metal present in toxic amounts into a stable, soluble complex that the body can excrete. Each ligand is chosen for a particular metal: D-penicillamine and desferrioxime B remove excess copper and iron, while EDTA is used for lead poisoning.
Option (1) cis-platin effectively inhibits the growth of tumours. — A correct application. cis-\( \ce{[Pt(NH3)2Cl2]} \) and related platinum complexes inhibit the growth of tumours.
Option (2) chlorophyll helps in photosynthesis — A correct application. Chlorophyll, the green pigment that absorbs light for photosynthesis, is a coordination compound of magnesium.
Option (3) desferrioxime B is used in treatment of lead poisoning — Not a correct application. Desferrioxime B removes excess iron and copper; lead poisoning is treated with EDTA, which binds \( \ce{Pb^2+} \) into a soluble complex.
Option (4) cyanocobalamine, antipernicious anemia factor is a coordination compound of Co — A correct application. Vitamin B12 (cyanocobalamin), which prevents pernicious anaemia, is a cobalt complex.
NCERT (2026-27 edition):
Importance and Applications of Coordination Compounds – “… Coordination compounds are of great importance in biological systems. The pigment responsible for photosynthesis, chlorophyll, is a coordination compound of magnesium. Haemoglobin, the red pigment of blood which acts as oxygen carrier is a coordination compound of iron. Vitamin B12, cyanocobalamine, the anti–pernicious anaemia factor, is a coordination compound of cobalt. Among the other compounds of biological importance with coordinated metal ions are the enzymes like, carboxypeptidase A and carbonic anhydrase (catalysts of biological systems). … There is growing interest in the use of chelate therapy in medicinal chemistry. An example is the treatment of problems caused by the presence of metals in toxic proportions in plant/animal systems. Thus, excess of copper and iron are removed by the chelating ligands D–penicillamine and desferrioxime B via the formation of coordination compounds. EDTA is used in the treatment of lead poisoning. Some coordination compounds of platinum effectively inhibit the growth of tumours. Examples are: cis–platin and related compounds.”